The latent heat is assumed to be released over a range of temperatures from a lower (solidus) temperature to an upper (liquidus) temperature. Smooth Latent Heat TransitionOptionally, you may specify a smooth transition from solidus to liquidus temperature using
Uθ=(LH) ξ3(10−15ξ+6ξ2) for θS≤θ≤θL,
where
Uθ
is the internal energy,
LH
is the latent heat, and
ξ=(θ−θS)(θL−θS)
. The above function is such that the first and second derivatives of
Uθ
are zero at
θS
and
θL
. The definition is intended to ramp up from one value to another. In
addition, you can extend the solidus-liquidus temperature interval using a scale factor,
f
, as follows:
θS_new=12[θS+θL−(θL−θS) . f]
θL_new=12[θS+θL+(θL−θS) . f]
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